The present invention relates to a color liquid crystal shutter matrix, and more particularly to a color liquid crystal shutter matrix of the type which comprises a liquid crystal panel with a liquid crystal sealed between transparent substrates, polarizing films mounted on the liquid crystal panel, a drive electrode assembly mounted in the liquid crystal pane and drivable by color image information corresponding to three colors R (red), G (green) and B (blue), and color filters mounted on the liquid crystal panel and composed of thin films containing dyes or pigments of R, G and B.
There have heretofore been known color image printers which read an image carried by a photographic film or an original, process the read image with an image processor comprising a microcomputer, and reproduces the processed image as a visible image.
One such color image printer comprises a three-color rotary color filter and a liquid crystal shutter matrix as disclosed in U.S. Pat. No. 4,605,972. Depending on color image information corresponding to three colors R, G and B, the three-color rotary color filter is rotated and the liquid crystal shutter matrix is energized to print a color image. The color image printer of this type is slow in printing speed.
Another known color image printer comprises a color liquid crystal shutter matrix which includes a drive electrode assembly mounted in a liquid crystal panel and drivable by color image information corresponding to three colors R, G and B and color filters mounted on the liquid crystal panel and composed of thin films containing dyes or pigments of R, G and B.
More specifically, as shown in FIG. 1 of the accompanying drawings, the color filters are composed of thin films 4a, 4b, 4c containing dyes or pigments corresponding to R, G and B, the color filters being mounted on a liquid crystal panel 2. The drive electrode assembly comprises a matrix of pixel electrodes 6a, 6b, 6c corresponding to R, G and B. The pixel electrodes 6a, 6b, 6c are arranged in arrays each including pixel electrodes 6a, 6b, 6c and extending in the direction in which a photosensitive medium is fed, i.e., in the direction indicated by the arrow X, and also in arrays each including pixel electrodes 6a or 6b or 6c and extending in the main scanning direction indicated by the arrow Y. The pixel electrodes 6a, 6b, 6c are selectively driven depending on color image information corresponding to R, G and B to drive the liquid crystal shutter matrix for reproducing a color image.
Psychological and physical researches of human vision indicate that the human eyes are most sensitive to green (G or magenta as a subtractive primary). In the known color printer, the pixel electrodes are identical in size and deal equally with R, G and B. The number per unit area of pixel electrodes for G, to which the human eyes are most sensitive, is the same as the number of pixel electrodes for each of the other colors of R and B. As a result, the image which is visually reproduced is relatively poor in fineness.